Self-matching fluid elements



p 13, 1966 R. w. WARREN 3,272,214

SELF-MATCHING FLUID ELEMENTS Filed Oct. 2. 1963 v 5 Sheets-Sheet 1INVENTOR, fl rMaA/a MFFE/V Sept. 13, 1966 R. w. WARREN SELF-MATCHINGFLUID ELEMENTS Filed Oct. 2, 1963 Z Sheets-Sheet 2 @rm/vM/nmem Sept 13,1966 w R N 3,272,214

SELF-MATCHING FLUID ELEMENTS Filed Oct. 2, 1963 f5 Sheets-Sheet 5INVENTOR, 6414mm h! we?! )4 7w- 1 BY 5%; I M a United States Patent O3,272,214 SELF-MATCHING FLUID ELEMENTS Raymond W. Warren, McLean, Va.,assignor to the United States of America as represented by the Secretaryof the Army Filed Oct. 2, 1963, Ser. No. 313,402 4 Claims. (Cl. 13781.5)

The invention described herein may be manufactured and used by or forthe Government of the United States of America for governmental purposeswithout the payment to me of any royalty thereon.

This invention relates to fluid amplifiers and, more particularly, toimpedance matched lock-on type fluid amplifier logic elements.

In the development of logic systems incorporating fluid amplification,it is necessary that the fluid elements produce their functions by beingmatchable to other elements or devices without excessive loss ofoperating pressures and without overloading any of the components. Thisis accomplished in this invention by maintaining the interactionchambers of these lock-on type amplifiers at ambient conditions. Mostlogic systems require the extensive use of logic elements, the mostcommon being the flip-flop, or bistable element, the AND and the OR. Forconvenience of manufacture and assembly, it is desirable that all inputand control jets be the same size and that all the power be applied withthe same pressure. Assuming the above conveniences, if a long string oflogic elements were connected in series with all power jets fed from thesame pressure source with the only outputs being the extreme outputs,the pressure would build up in the system until only the last few unitsin a series would have suflicient pressure drop to cause the flownecessary for operation.

The most desirable situation would be to have the same constant pressuredrop across each power jet nozzle in order to produce a constant flow.To do this, each succeeding control nozzle should present a constantload regardless of whether the succeeding power jet is flowing acrossthe control nozzle or not.

If outputs are placed in the system other than at the extreme outputs,they would have to be adjusted in accordance with. the pressure drop toallow sufficient flow and pressure to escape to permit operation but notto the extent that there is insufficient flow to control the next unit.This can readily be done in simple systems. In complex systems where thepressure pattern is not necessarily repeatable, but is somewhat sporadicas a result of the operation of various elements of the system, it canbe seen that simple pressure bleeds are inadequate to impedance match acomplex system. Since a pressure differential is required to hold thepower jet against the wall and as this pressure differential changes asthe unit is switched, a pressure release can remove energy needed tocontrol succeeding units.

It is, therefore, an object of this invention to provide fluid logicelements which are capable of being impedance matched with other fluidelements.

Another object of this invention is to provide fluid logic elements inwhich all input power and control jets are the same size.

Still another object of this invention is to provide a fluid logicsystem in which all the power jets are supplied with the same fluidpressure.

A further object of this invention is to provide fluid elements for afluid logic system in which all of the elements in the system havesuflicient pressure drop to cause fluid flows necessary for operation Astill further object of this invention is to provide fluid logicelements for a fluid logic system in which each succeeding controlnozzle presents a constant load regardless of whether the succeedingpower jet is flowing across the control nozzle or not.

Another object of this invention is to provide for control of reflectedsonic waves and fluid pulses.

The specific nature of the invention, as well as other objects, uses andadvantages thereof, will clearly appear from the following descriptionand from the accompanying drawing, in which:

FIG. 1 is a plan view of an AND fluid logic element;

FIG. 2 is a plan view of a first embodiment of an OR fluid logicelement;

FIG. 3 is a second embodiment of an OR fluid logic element;

FIG. 4 is an embodiment of a bistable fluid element including multipleinputs and multiple outputs; and

FIG. 5 is a plan view of another embodiment of a bistable fluid elementincorporating multiple inputs and multiple outputs.

Turning now to FIG. 1 in which is shown an AND fluid logic circuit, thecircuit element is typically made up of a laminate of plastic material,such as Lucite, or of metal or any other desired material. The toplamina is a cover plate through which the various inputs to the logicelement are applied. A layer is machined, drilled, or etched orotherwise grooved to present the opening therein which enables the fluidstreams to exit through a selected passage depending upon the presenceof an input stream through either or both of said input nozzles. Thelower surface has no openings therein so as to seal the units. The fluidstreams are confined between the top and bottom surfaces so as to flowthrough the passages provided in the central section between such topand bottom surfaces.

The logic element illustrated in FIG. 1 is an AND circuit 10 having apair of input nozzles 11 and 12 which are substantially perpendicular toeach other. These nozzles are connected to input signals through opening13 to a source of A signals and through opening 14 to a source of Bsignals, respectively.

The input nozzles 11 and 12 are directed intoan interaction chamber 15.Also opening into the interaction chamber 15 are the three receivers 18,23 and 26 as well as the channels 32 and 33 which maintain theinteraction chamber 15 at the ambient condition. The first receiver 18is positioned so as to receive the fluid flow through nozzle 12 with itsB logic information in the absence of A logic information. The centralreceiver 26 is positioned so asto receive the fluid flows throughnozzles 11 and 12 when both the A and B sources enable fluid flow. Thethird receiver 23 is positioned so as to receive fluid flow throughnozzle 11 in the presence of A fluid flows during the absence of B fluidflows.

The first receiver 18 is bounded on one side by a lock-on accomplish ORlogic functions.

wall 16 which extends to the egress of nozzle 11 to provide a boundaryfor interaction chamber 15. Receiver 18 is bounded on its opposite sideby a wall 17 which is a side of the first divider 19 the sides of whichconverge at a point 35. The second receiver 26 is bounded by a secondand third divider 27 and 28 respectfully. The side walls of divider 27converge at a point 29 in the interaction chamber 15. A first bleederchannel 32 is defined by the sides of dividers 19 and 27 which face eachother. Channel 32 is opened into the interaction chamber between points35 and 29. Second receiver 26 opens into interaction chamber 15 betweenpoint 29 and a point 31 which is the point of convergence of divider 28.The third receiver 23 is defined by a lock-on wall 21. Wall 22 comes toa point of a divider which separates the third receiver from the secondchannel 33 which connects the interaction chamber 15 to the ambientcondition.

The letter W represents a nozzle Width such as the width of nozzle 11 or12 and the remainder of the openings into the interaction chamber aredesignated as 2W to indicate that an optimum size for such openings istwice the nozzle width.

The bleeds in the AND unit are positioned to prevent simultaneoussignals in the AB and AE or BE channels when the A and B signals are notequal or may be only a fraction of each other.

FIG. 2 shows an OR fluid logic circuit incorporating the principles ofthis invention. The OR logic element '85 is provided with a plurality ofinputs 86, 87, 88 and 89 which provide A, B, C, or D logic informationrespectfully. The sources of such logic information are not shown butcan be connected through the top layer of the laminated body 85. Thefour input channels are directed toward interaction chamber 91. It isobvious that any number of a plurality of input channels may be used toIn receiving position of any signal applied through any of the inputchannels is a receiver 92 which is defined by the dividers 95 and 96.These dividers enter into the interaction chamber 91 to further define afirst passage 93 on the side of divider 95 which is opposite to thereceiver 92 and a second channel 94 which is on the opposite side ofdivider 96 from receiver 92. These channels 93 and 94 provide an openingfrom the interaction chamber 91 to the ambient condition. A pair ofcusps 97 and 98 are provided at the terminus of the extreme inputchannels to reinforce the bleeding off of excessive fluid which wouldotherwise be directed into the receiver 92. The points of convergence ofdividers 95 and 96 are located in the interaction chamber 91 and formwith the points of the cusps 97 and 98 and the points defining thedownstream end of the input channels, the interaction chamber 91. Therelationship of the sizes of the openings into the interaction chamber15 is not critical. However, a very good relationship of sizes would bethat the width of the receivers be approximately twice the width of theinput channels.

The OR circuit shown in FIG. 3 differs from the OR shown in FIG. 2 inthat the channel 107 which connects the interaction chamber 105 to theambient condition is located between the input channels 101, 102, 103and 104. The four illustrated inputs represent A, B, C, and D logicinformation. The extreme sides of the input channels 101 and 104 tapertoward the interaction chamber 105 to become parallel and form thereceiver 106. The presence of the signal in receiver 106. gives thelogic information that a signal is present in input channel A or B or Cor D. As in FIG. 2, the number of input channels is limited only by thespace available within the structure 100.

The bistable fluid amplifier 109 in FIG. 4 has a pair of OR circuitsused as the controls therefore, and a plurality of output passages areprovided for each of the two receivers. A power stream is introducedthrough channel 110 through the tubing 111 connected thereto from apower source not shown. The tubings 111 are representative of the tubingemployed for the power stream, the control fluid and the outputs. Thepower stream enters through nozzle 112 into the interaction chamber 113into which are also directed left control nozzle 114 and a right controlnozzle 115. Opening to the ambient condition through the upper surfaceare holes 116, 117 and 118 which are positioned at the confluence of theplurality of control inputs and at the divider 127 where the leftreceiver 128 and the right receiver 129 are in communication with theinteraction chamber 113. There are three right control inputs 121, 122and 123 which introduce control information into the right controlnozzle 115. Also shown are three left control inputs 124, 125 and 126which introduce logic information into the left control nozzle 114. Theleft receiver 128 is divided into three out-put channels 131, 132 and133 so that a plurality of further logic elements or loads can beconnected thereto. Also, since these elements are tailored to thespecific needs of the system in which they are utilized, some of theoutputs can be connected to the ambient condition if such is needed forimpedance matching. Likewise, right receiver 129 is divided into threeoutputs 134 and 135 and 136 for the same reason as the left receiver128.

In the cut away sections top layer 137 and center layer 139 withsecuring means 138 for tubing 111 provided within the body of theelement 109 for each of the several tubings 111. The securing means 138is basically a stepped opening within the body, usually within thecenter layer 139, shaped to conform with the outside dimension of thetubing 111 and being of a dimension that is slightly smaller incircumference in the tubing 111 so that once the tubing is insertedwithin the securing means 138, it cannot be withdrawn accidently nor inthe normal use of the logic element. The smallest dimension of thestepped opening which contacts the tubing 111 is substantially the samefor all of the steps. The center bore of the tubing 111 is the same sizeand shape as the channels which form the power stream, the controlinputs and the receiver outputs so that minimum impedance to fluid flowis offered at the junction thereof.

With the power stream introduced to the interaction chamber 113 throughpower nozzle 112, signals into any of the OR inputs 121, 122 or 123 willproduce a control pulse to switch the power stream into receiver 128.Likewise, a single input or a plurality of inputs into control lines124, or 126 will produce a control signal to switch the fluid powerstream into receiver 129. As illustrated, the two receivers have eachthree output channels connected thereto so as to provide simultaneoussignals to a plurality of load devices connected thereto. The bleederholes 116, 117 and 118 which are perpendicular to the fluid flow in thechannels thereunder, provide for an equalization of pressure throughoutthe system whereby this logic element 109 can be impedance matched toany output device connected thereto. The special configuration of theside walls of the input channels and the receiver channels enhances thesmooth operation of this device.

FIG. 5 shows a second bistable fluid amplifier which differs from theamplifier in FIG. 4 by an alternate method of providing the ambientcondition in the interaction chamber thereof. In the fan-in fan-outfluid logic element 140 is found a power nozzle 141 directed into aninteraction chamber 142 which also has directed thereinto a left controlnozzle 143 and a right control nozzle 144. Through the top lamina of alaminated package such as in the other species of this invention, arebleeder holes 145 for the left control means and a right bleeder hole146 for the right control means. A plurality of input channels areprovided as channels 147, 148 and 149 which join in an OR configurationto supply left control nozzle 143 with control signals. The rightcontrol means is likewise provided with a plurality of input channels151,

152 and 153, for example, which are joined in an OR circuit to provideinput signals to the right control nozzle 144. The interaction chamber142 is maintained at the ambient condition by left bleeder channel 154and right bleeder channel 155. The divider which is symmetric about thecenter line of the power nozzle 141 is shaped so as to present a concavesurface 156 toward fluid power nozzle 141. Also symmetric about thecenter line of power nozzle 141 are receivers 157 and 158 which areseparated by the divider and begin in the interaction chamber 142. Attheir other ends, the receivers are branched into a plurality of outputchannels 161, 162 and 163 for left receiver 157 and channels 164, 165and 166 for right receiver 158. It is seen that connectors for thetubings 111 are the same as the connectors 138 in FIG. 4.

The sidewalls of the input channels converge so as to prevent reflectionof waves flowing therethrough and to sharpen the wave front of suchwave. Otherwise, entrainment would render the wave ineffective as anactive signal. The receiving channels and bleed channels diverge toprevent reflections and to match the outputs.

The walls of receiver 128 and 129 as in FIG. 4, diverge at such a ratethat the flow will not separate from the wall, thus providing a uniformwave front. Essentially equal flow is obtained in each output by makingthe outer channels wider to compensate for the reduced flow in theboundary layer adjacent to the diverging walls. By this means, theoutput flows can be divided into any proportions desired.

Thus, it is seen that I have provided a related group of logic elementswhich can be combined to perform complex logic operations in computerapplications. For example, the AND circuit of FIG. 1 can have for itsinputs the outputs of the OR circuits shown in FIG. 2 and the flip-flopin FIG. 4 the like to produce a system which is capable of functioningas an adder and the like.

It is further seen that by having bleed openings at right angles to thevelocity vector, the velocity will carry the flow (kinetic energy) pastthe bleed while the pressure (potential energy) which is nownondirectional Will cause flow out of the bleed. Thus, if the rig-htangle bleed is in a high velocity region it is possible to regulate thepressure while providing sufficient flow to control the succeedingelement.

When an element is switched from one output passage to another initiallythere is very little resistance to flow,

velocity is high and static pressure is low. When the high velocity flowencounters the resistance load of the next control nozzle, the flowwhich cannot pass through the nozzle at the instantaneous pressure ratioconverts to an additional pressure raising the pressure ratio and givinga high flow through the control nozzle, thus switching the unit.

The pressure also proceeds upstream in the subsonic flow and wouldchange the pressure ratio over the previous power jet or cause flow outthe wrong inlet. The openings at essentially right angles to the flowpermit the static pressure to release to ambient with an ensuing flow.This loss of flow and energy is not deleterious at this time as thedesired objective of controlling the succeeding element has beenachieved, and it serves the useful purpose of maintaining the desiredpressure ratio and flows at the nozzles. The fluid logic element becomesself-adaptive.

So, any existing logic system consisting of flip-flop, AND and ORelements can be assembled from fluid logic elements with the same sizenozzles supplied from the same pressure source and operated withoutfurther impedance matching.

The bleed channels in the AND circuit of FIG. 1 and the OR circuit ofFIGS. 2 and 3 accomplish the same purpose by the discreet selection ofopening into the interaction chamber and the flaring of the bleedchannel in the direction away from the interaction chamber.

It will be apparent that the embodiments shown are only exemplary andthat various modifications can be made in construction and arrangementwith the scope of the invention as defined in the appended claims.

I claim as my invention:

1. In a fluid bistable amplifier:

(a) fluid power source for producing a fluid stream,

(b) a power nozzle connected to said power source,

(o) a plurality of input channels,

(d) an equal plurality of sources of fluid signals connected one to eachof said input channels,

(e) some of said plurality of input channels converging to a firstcontrol nozzle,

(f) the remainder of said input channels converging to a second controlnozzle,

(g) an interaction chamber,

(h) said control nozzles being axially aligned and oppositely directedinto said interaction chamber,

(i) said power nozzle being perpendicular to said control nozzles anddirected into said interaction cham ber,

(j) a pair of receiver means,

(k) each of said receiver means diverging into a plurality of outputmeans,

(1) individual ones of said plurality of output means being dimensionedto receive a predetermined proportion of said power stream,

(in) and bleeder means perpendicular to the fluid flow at the confluenceof the input channels and of the receiver means.

2. The fluid amplifier according to claim 1, wherein:

(a) the sidewalls of said input channels converge toward saidinteraction chamber by the amount necessary to prevent reflection ofwaves flowing therethrough, and

(b) the walls of said receiver means diverge in the downstream directionat the rate necessary to prevent flow separation from said walls toprovide a uniform wave front thereby enabling the output flows to bedivided into any proportions desired.

3. In a fluid bistable amplifier:

(a) fluid power source for producing a fluid stream,

(b) a power nozzle connected to said power source,

(0) a plurality of input channels,

(d) an equal plurality of sources of fluid signals connected one to eachof said input channels,

(e) some of said plurality of input channels converging to a firstcontrol nozzle,

(f) the remainder 'of said input channels converging to a second controlnozzle,

(g) an interaction chamber,

(h) said control nozzles being axially aligned and oppositely directedinto said interaction chamber,

(i) said power nozzle being perpendicular to said control nozzles anddirected into said interaction chamber,

(j) a pair of receiver means,

(k) each of said receiver means diverging into a plurality of outputmeans,

(1) individual ones of said plurality of output means being dimensionedto receive a predetermined proportion of said power stream,

(m) a bleeder means perpendicular to the fluid flow at the confluence ofeach of the input channels,

(n) a concave surfaced divider between said receiver means alignedaxially of said power nozzle,

(0) and a pair of bleeder channels connected to opposite sides of saidinteraction chamber aligned with said concave surface.

4. The fluid amplifier according to claim 3 wherein:

(a) the sidewalls of said input channels converge toward saidinteraction chamber by the amount necessary to prevent reflection ofwaves flowing therethrough, and

(b) the walls of said receiver means diverge in the down streamdirection at the rate necessary to prevent flow separation from saidwalls to provide a uniform wave front thereby enabling the output flowsto be divided I 8 FOREIGN PATENTS into y proportions desired- 5 FluidJet Control Devices, A.S.M.E., Nov. 28, 1962; p.

References cued by the Examiner Fluid Logic Devices and Circuits,Transactions of the UNITED STATES PATENTS 7 Society of InstrumentTechnology, Mitchell et al., Feb. 12/1962 Riordan 137 s1.5 26, 1963; PP-3, 6W1 10/1963 Warren et a1. X 10 Harry Dlamond Laboratories Report,TR-1114, Fluld 1/1964 Sewers 137 81.5 X Amplification, No. 9 LogicElements, E. V. Hobbs, 2 19 4 Horton 137 1;5 Mali 8, 1963, P 16, I

i gzfgf M. CARY NELSON, Primary Examiner.

6/1965 Phillips 137-815 15 s. SCOTT, Assistant Examiner.

1. IN A FLUID BISTABLE AMPLIFIER: (A) FLUID POWER SOURCE OF PRODUCING AFLUID STREAM, (B) A POWER NOZZLE CONNECTED TO SAID POWER SOURCE, (C) APLURALITY OF INPUT CHANNELS, (D) AN EQUAL PLURALITY OF SOURCES OF FLUIDSIGNALS CONNECTED ONE TO EACH OF SAID INPUT CHANNELS, (E) SOME OF SAIDPLURALITY OF INPUT CHANNELS CONVERGING TO A FIRST CONTROL NOZZLE, (F)THE REMAINDER OF SAID INPUT CHANNELS CONVERGING TO A SECOND CONTROLNOZZLE, (G) AN INTERACTION CHAMBER, (H) SAID CONTROL NOZZLES BEINGAXIALLY ALIGNED AND OPPOSITELY DIRECTED INTO SAID INTERACTION CHAMBER,(I) SAID POWER NOZZLE BEING PERPENDICULAR TO SAID CONTROL NOZZLES ANDDIRECTED INTO SAID INTERACTION CHAMBER, (J) A PAIR OF RECEIVER MEANS,